From: Matthias Maier <tamiko@43-1.org>
Date: Thu, 12 Jan 2017 22:20:22 +0000 (-0600)
Subject: CMake: Refactor macros and augment comment
X-Git-Tag: v8.5.0-rc1~254^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6c56cdeee568ca65dd90fb249ce34de82e6a87f6;p=dealii.git

CMake: Refactor macros and augment comment
---

diff --git a/cmake/configure/configure_boost.cmake b/cmake/configure/configure_boost.cmake
index 45a88e6001..aac240b3d1 100644
--- a/cmake/configure/configure_boost.cmake
+++ b/cmake/configure/configure_boost.cmake
@@ -22,6 +22,31 @@ SET(DEAL_II_WITH_BOOST ON # Always true. We need it :-]
   )
 
 
+MACRO(FEATURE_BOOST_CONFIGURE_COMMON)
+  #
+  # Boost version 1.62 - 1.63 checks for the availability of "emplace_hint"
+  # incorrectly: It tests for the preprocessor define
+  # BOOST_NO_CXX11_HDR_UNORDERED_MAP in .../boost/serialization/map.h
+  # thinking that that this define is characteristic for the presence of
+  # std::(multi)map::emplace_hint. This is generally correct, except for
+  # GCC before 4.8, for which the preprocessor variable is defined, but the
+  # function does not exist [1].
+  #
+  # Thus, simply define a BOOST_NO_CXX11_HDR_UNORDERED_MAP if the gcc
+  # compiler version is less than 4.8.
+  #
+  # [1] https://svn.boost.org/trac/boost/ticket/12755
+  #
+  IF( CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND
+      CMAKE_CXX_COMPILER_VERSION VERSION_LESS "4.8" )
+    LIST(APPEND BOOST_DEFINITIONS "BOOST_NO_CXX11_HDR_UNORDERED_MAP")
+    LIST(APPEND BOOST_USER_DEFINITIONS "BOOST_NO_CXX11_HDR_UNORDERED_MAP")
+  ENDIF()
+
+  ENABLE_IF_SUPPORTED(BOOST_CXX_FLAGS "-Wno-unused-local-typedefs")
+ENDMACRO()
+
+
 MACRO(FEATURE_BOOST_CONFIGURE_BUNDLED)
   #
   # Add rt to the link interface as well, boost/chrono needs it.
@@ -34,7 +59,7 @@ MACRO(FEATURE_BOOST_CONFIGURE_BUNDLED)
     ENDIF()
   ENDIF()
 
-  ENABLE_IF_SUPPORTED(BOOST_CXX_FLAGS "-Wno-unused-local-typedefs")
+  FEATURE_BOOST_CONFIGURE_COMMON()
 
   SET(BOOST_BUNDLED_INCLUDE_DIRS ${BOOST_FOLDER}/include)
 
@@ -47,19 +72,6 @@ MACRO(FEATURE_BOOST_CONFIGURE_BUNDLED)
     LIST(APPEND BOOST_DEFINITIONS "BOOST_ALL_NO_LIB")
     LIST(APPEND BOOST_USER_DEFINITIONS "BOOST_ALL_NO_LIB")
   ENDIF()
-
-  #
-  # Our bundled boost version 1.62 checks for the availability of
-  # "emplace_hint" incorrectly. Thus, simply define
-  # BOOST_NO_CXX11_HDR_UNORDERED_MAP if the gcc compiler version is less
-  # than 4.8.
-  #
-  IF( CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND
-      CMAKE_CXX_COMPILER_VERSION VERSION_LESS "4.8" )
-    LIST(APPEND BOOST_DEFINITIONS "BOOST_NO_CXX11_HDR_UNORDERED_MAP")
-    LIST(APPEND BOOST_USER_DEFINITIONS "BOOST_NO_CXX11_HDR_UNORDERED_MAP")
-  ENDIF()
-
 ENDMACRO()
 
 MACRO(FEATURE_BOOST_FIND_EXTERNAL var)
@@ -76,22 +88,12 @@ MACRO(FEATURE_BOOST_FIND_EXTERNAL var)
       MESSAGE(STATUS "Boost version 1.58 is not compatible with deal.II!")
       SET(${var} FALSE)
     ENDIF()
-
-    #
-    # Newer boost versions check for the availability of "emplace_hint"
-    # incorrectly. Thus, simply define BOOST_NO_CXX11_HDR_UNORDERED_MAP if
-    # the gcc compiler version is less than 4.8.
-    #
-    IF( CMAKE_CXX_COMPILER_ID MATCHES "GNU" AND
-        CMAKE_CXX_COMPILER_VERSION VERSION_LESS "4.8" )
-      LIST(APPEND BOOST_DEFINITIONS "BOOST_NO_CXX11_HDR_UNORDERED_MAP")
-      LIST(APPEND BOOST_USER_DEFINITIONS "BOOST_NO_CXX11_HDR_UNORDERED_MAP")
-    ENDIF()
   ENDIF()
 ENDMACRO()
 
+
 MACRO(FEATURE_BOOST_CONFIGURE_EXTERNAL)
-  ENABLE_IF_SUPPORTED(BOOST_CXX_FLAGS "-Wno-unused-local-typedefs")
+  FEATURE_BOOST_CONFIGURE_COMMON()
 ENDMACRO()